2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/44064From astrophysics there are indications that the finestructure constant $α$ has changed during the past 10 billion years. Within grand unification one can deduce that also the QCD scale has changed. Tests for a time variation of this scale are described. The result of the new experiment in Munich is discussed.6 pagesHigh Energy Physics - Phenomenologytext